Context Window

Compare

Claude Opus 4.7 (Fast) vs Grok 4 1 Fast Reasoning

This page is context-first: how much text each model can take in one request. Full specs adds capabilities and limits; the pricing matrix below is only about $/million tokens from hosts that list both models.

Anthropic

Model

Claude Opus 4.7 (Fast)

Image inputTool calling

Context window

1M

1,000,000 tokens · ~750K words

Model page
Xai

Model

Grok 4 1 Fast Reasoning

Tool calling

Context window

131K

131,072 tokens · ~98K words

Model page

Context window · side by side

Bar length is relative to the larger of the two windows (100% = max of this pair). This is not pricing.

Claude Opus 4.7 (Fast)1M
Grok 4 1 Fast Reasoning131K

Claude Opus 4.7 (Fast) has about 7.6× the context window of the other in this pair.

Token calculator →Memory savings →

Claude Opus 4.7 (Fast) has 662% more context capacity (1000K vs 131K tokens).

Quick verdicts

Short takeaways — validate with your own workloads.

  • Long document processing

    Use Claude Opus 4.7 (Fast). Its 1000K context fits entire documents without chunking (vs 131K).

  • Long output (reports, code files)

    Use Grok 4 1 Fast Reasoning. Its 131K max output lets you generate complete artifacts in one request.

Full specs

Context, output, capabilities, and dates. Green highlights the favorable value where we compute a winner.

SpecClaude Opus 4.7 (Fast)Grok 4 1 Fast Reasoning
Context window1,000,000 tokens (1000K)131,072 tokens (131K)
Max output tokens128,000 tokens (128K)131,072 tokens (131K)
Speed tierDeepDeep
VisionYesNo
Function callingYesYes
Extended thinkingYesYes
Prompt cachingYesYes
Batch APIYesNo
Release dateMay 2026N/A

Pricing matrix

Dollar rates only: hosts that list both models, per 1M tokens. For how much text fits, use the context section above — not this table.

ProviderClaude Opus 4.7 (Fast) inClaude Opus 4.7 (Fast) outGrok 4 1 Fast Reasoning inGrok 4 1 Fast Reasoning out
Azure——$0.200/M$0.500/M
Google Vertex——$0.200/M$0.500/M
Xai——$0.200/M$0.500/M

Frequently asked questions

Claude Opus 4.7 (Fast) has a larger context window: 1000K tokens vs 131K. For long documents, large codebases, or extended agent sessions, the larger context window reduces the need to chunk inputs or summarize history.

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Repeated info
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